Field of the Invention
The present invention relates to a driving force control system for an automotive vehicle, and specifically to a driving force control system suitable for a hybrid vehicle employing a parallel hybrid system using both an internal combustion engine and an electric motor/generator as a propelling power source or an electric vehicle.
In recent years, there have been proposed and developed various parallel hybrid vehicles propelled by an internal combustion engine and/or an electric motor. In such parallel hybrid vehicles, it is desirable to produce a driving force (or driving torque) corresponding to both a driver's required driving force and required generated electric energy by operating an internal combustion engine with the lowest fuel consumption (the best fuel economy or the best engine efficiency) during an engine-propelled vehicle driving mode. On the other hand, during a motor-propelled vehicle driving mode, it is desirable to produce a driving force (or driving torque) corresponding to a driver's required driving force by operating an electric motor/generator with the lowest electric power consumption (the best motor/generator efficiency).